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    I don't understand. You question asked "I want...

    I don't understand. You question asked "I want to use two pressure sensors with two teensy 3.6".

    Now you're saying you only have one Teensy 3.6?
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    Assuming the motor is controlled by a simple...

    Assuming the motor is controlled by a simple on/off digital signal, probably the simplest and (maybe) most reliable way would be to use an "open collector" approach to connect both output signals. ...
  3. I believe most of the AVR chips have TTL level...

    I believe most of the AVR chips have TTL level inputs which work with 3.3V signals even when the AVR runs at 5V. So my best guess is you don't need the level shifter and this is probably a software...
  4. It really depends on how well (or poorly) the...

    It really depends on how well (or poorly) the code makes use of the cache.

    Teensy 3.6 has an 8K cache. Teensy 4.1 has a pair of 32K caches, but cache misses have a much larger impact on...
  5. RAM is being used for code. If you install...

    RAM is being used for code. If you install 1.54-beta7, the memory usage info is improved to show how the memory is being used. 1.53 uses Arduino's default memory summary which can't show more...
  6. Wow, that's an old part. I'm assuming you mean...

    Wow, that's an old part. I'm assuming you mean this, right?

    https://www.ti.com/product/DAC811

    The good news is it uses TTL level inputs, where anything over 2V is logic high and anything under...
  7. I'm afraid only Apple can solve this. It's a...

    I'm afraid only Apple can solve this. It's a kernel level problem, which is way out of my league! Teensyduino doesn't install any drivers on MacOS. Nothing runs in kernel space, or even with root...
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    void setup() { analogWriteFrequency(2,...

    void setup() {
    analogWriteFrequency(2, 5000000);
    analogWrite(2, 128);
    }

    void loop() {
    }


    24735
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    Normally if your program reads the same variable...

    Normally if your program reads the same variable more than once, you would want the compiler to perform only 1 read and keep the data in a CPU register so the next access is faster. That's exactly...
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    // PLAY START if (buttons[0]->wasPressed())...

    // PLAY START
    if (buttons[0]->wasPressed()) {
    // <---- Try adding the delay here!
    sendMMC(1, (uint8_t*)"\x02"); // Play
    }
  11. Nearly all other Arduino boards use 12 Mbit/sec...

    Nearly all other Arduino boards use 12 Mbit/sec USB speed, and most of those have a combination of slow processors and inefficient software that can't manage to use even half that speed. Teensy 4.0...
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    No, not with Teensy 4.0. This is true only for...

    No, not with Teensy 4.0.

    This is true only for Teensy 3.6 when running faster than 120 MHz. Higher clock speeds on Teensy 3.6 use a special "HSRUN" mode. Internal EEPROM writing is not possible...
  13. Glad it turned out to be just a bad hub. One...

    Glad it turned out to be just a bad hub.

    One of the hubs I have on my workbench feels like they skimped on the power supply or capacitors. It usually works but sometimes when plugging in a board...
  14. You need to turn on the clock to the SPDIF...

    You need to turn on the clock to the SPDIF peripheral before you attempt to use it.

    Here's your program with the clock config copied from the Audio library. It starts up with those 4 lines...
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    Again, I suspect you're not anticipating the load...

    Again, I suspect you're not anticipating the load (input impedance) of whatever other audio gear will receive your signal.

    This sort of simple all-passive (no additional opamps, transistors, etc)...
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    10uF is generic advice given without knowledge of...

    10uF is generic advice given without knowledge of the input impedance of whatever will receive the signal.

    10uF is also a very widely used and inexpensive capacitor.




    A simple...
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    Any chance you can try running the test on Linux...

    Any chance you can try running the test on Linux or Windows?

    When Teensy 4.0 transmits at max speed to MacOS, I've seen issues (and very high CPU usage) that don't happen on Linux and Windows. ...
  18. Can't really comment on that code, but the...

    Can't really comment on that code, but the documentation for the registers is an easy question. It's in the datasheet, pages 129-137, and also on page 409.
    ...
  19. Nope. Atmel put timers 0, 1, 3 and 4 into this...

    Nope. Atmel put timers 0, 1, 3 and 4 into this chip. Why they skipped timer2, I don't know and can only guess.

    But 2 likely guesses would be they made a mistake that ruined timer2 and just...
  20. A couple years ago I made a I2C test board with...

    A couple years ago I made a I2C test board with several devices. One was a Garmin lidar sensor. It needed 5V power but worked fine with 3.3V signals on I2C.

    24696

    Difficult to know if you...
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    I tried it just now on a Teensy 4.0. The code...

    I tried it just now on a Teensy 4.0. The code needs a minor edit, since the first if condition doesn't allow OUTPUT_1 to OUTPUT_7. To be used within a normal program, the function needs a different...
  22. That's normal, assuming you're measuring ohms...

    That's normal, assuming you're measuring ohms with an ordinary multimeter. The ohms measurement is done by sending a DC current through the circuit and measuring the resulting DC (or average)...
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    Now, looking at your picture and focusing only...

    Now, looking at your picture and focusing only the right hand side where the LEDs are lit up, it looks like the widest part is about 60 pixels and I counted 42 rows. So in that Processing code,...
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    You have basically 2 choices. You need to...

    You have basically 2 choices. You need to somehow map the original video pixels onto your irregular shape pixels.

    Most people would do this on the PC side. You would to need to modify...
  25. Sadly, there is no way to do that. NXP simply...

    Sadly, there is no way to do that. NXP simply did not provide a signal path inside the chip for the Wire SDA & SCL signals to route to pins 24 & 25 where the Wire2 SDA2 & SCL2 signals are.

    To be...
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    Sounds like I need to get the test running here,...

    Sounds like I need to get the test running here, maybe over the weekend. I've not managed to keep up with this thread over the last several days. Any chance I can talk you into giving me a quick...
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    The other possible voltage regulator issue I can...

    The other possible voltage regulator issue I can see is the output capacitor. All LDO type regulators need a certain range of capacitor for stability. LDOs aren't inherently stable like standard...
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    You're talking about the voltage regulator on...

    You're talking about the voltage regulator on Sparkfun's ML carrier board, right?

    Their schematic says the part number is AP7361C-33FGE. Here's the part at Digikey. ...
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    This recent reply was spam.

    This recent reply was spam.
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    I looked briefly at your pull request. You've...

    I looked briefly at your pull request. You've made choices which require a massive number of changes throughout all the files. :(




    The very first step is to look for whether you're getting...
  31. You're not getting clocks on pins 3 & 4 because...

    You're not getting clocks on pins 3 & 4 because you have 2 copies of AudioInputI2S.



    // GUItool: begin automatically generated code
    AudioInputI2S i2s1; //xy=275,91
    AudioInputI2S i2s2;...
  32. Those connections appear to be correct. ...

    Those connections appear to be correct.




    To connect 4 of those boards, I would first try using AudioOutputI2SOct, which is i2s_oct in the design tool.

    Then for wiring, I would their clocks...
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    Yes, I can confirm the Teensy 4.1 cards got off...

    Yes, I can confirm the Teensy 4.1 cards got off to a rough start. PJRC has been running short-staffed since March 2020. Teensy 4.1 was released in May 2020. Several compromises had to be made. ...
  34. Use the audio library! Here's a 31 tutorial. ...

    Use the audio library!

    Here's a 31 tutorial.

    https://www.pjrc.com/store/audio_tutorial_kit.html

    You can probably skip a lot of this material. Read the first part of section 2 so you...
  35. So many reasons for the code size difference.......

    So many reasons for the code size difference....

    1: Compiler optimization: Arduino Mega optimizes for smallest code size. On AVR (and on ARM M0 chips), speed isn't much different. Teensy 3.5...
  36. As as a matter of technical terminology, this...

    As as a matter of technical terminology, this type of connection is called a "bus". The same data is transmitted from Teensy to all displays. Per-display control signals tell each display whether...
  37. You're probably experiencing "signal quality"...

    You're probably experiencing "signal quality" issues. It's a common problem when transmitting fast digital signals along long wires to multiple devices.




    Teensy's SPI port is capable of...
  38. While polarized vs nonpolar isn't important, this...

    While polarized vs nonpolar isn't important, this capacitor should be a ceramic or plastic film type, because those have the lowest impedance at higher frequencies. Aluminum electrolytic and...
  39. Calling SPI.setClockDivider() in setup() will not...

    Calling SPI.setClockDivider() in setup() will not have any effect. Each library sets the speed with SPI.beginTransaction() every time it communicates with the display. Any setting done with...
  40. It's not a polarized capacitor. There is no "+"...

    It's not a polarized capacitor. There is no "+" or "-" shown on the schematic.

    https://www.pjrc.com/teensy/td_libs_MIDI_sch_t3.png
  41. 5 files can work from a flash memory chip. ...

    5 files can work from a flash memory chip.

    Today the WAV file player doesn't buffer enough to allow 5 to work simultaneously from a SD card. SD cards have far too much random access latency.
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    Just use the Arduino attachInterrupt function,...

    Just use the Arduino attachInterrupt function, like this



    int count = 0;

    void setup() {
    pinMode(21, INPUT_PULLDOWN);
    attachInterrupt(digitalPinToInterrupt(21), myfunction, RISING);
    }
  43. Probably a ground loop problem. Best way to...

    Probably a ground loop problem. Best way to troubleshoot is listening with good headphones plugged directly into the audio shield. Maybe also power Teensy from a battery and disconnect USB and...
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    Usually connecting 3.3V digital signals between...

    Usually connecting 3.3V digital signals between separately powered boards is fine if their power supplies are within 0.3 volts of each other. While I don't know anything about this other circuitry...
  45. Yup, that sure sounds like something is shorting...

    Yup, that sure sounds like something is shorting out the 3.3V power. I'd start by measuring the actual voltage on 3.3V to GND.

    Usually a very low voltage, like under 0.1 volt, means the short is...
  46. Difficult to give an answer to a question which...

    Difficult to give an answer to a question which was never really a question in the first place. But nice try anyway!

    Specifically this...



    ... is lacking any sort of detail about what won't...
  47. I added "When hard-wiring a cable, check the...

    I added "When hard-wiring a cable, check the pinout as wire colors inside USB cables may not follow conventions" to the troubleshooting tip about swapping D+ and D-.
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    Usually this works, but if the 3.3V power supply...

    Usually this works, but if the 3.3V power supply starts up too slowly Teensy 4.1 can fail to boot up because power is seen on the 3.3V pins before SNVS reached about 1 volt.
  49. Have you tried using the existing SD library? ...

    Have you tried using the existing SD library? I'm pretty sure it does initialization at slow speed for compatibility with these sorts of cards.

    But if you *really* want to dive into writing your...
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    Almost all countries charge tariffs, vat or tax,...

    Almost all countries charge tariffs, vat or tax, and sometimes extra fees for handling customs. Those taxes, tariffs & fees are not included in the amount you pay when ordering. Usually the...
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